Section: Regular Expression Patterns

Regular Expression Patterns

This section provides a brief overview of regular expressions. For more in depth coverage there are excellent book (e.g., http://www.oreilly.com/catalog/regex/) resources.

Here are some example patterns and a description of what they will match:
Pattern Description

some string Will match match any occurrence of:"some string". e.g.:
"Here is some string" will match.
"Here is some string in the middle of the text" will match.
"some string at the beginning" will match.

^some string Will match "some string" at the beginning of the text:
"Here is some string" will not match.
"some string at the beginning"will match

some string$ Will match "some string" at the end of the text:
"Here is some string" will match.
"some string at the beginning" will not match.

^some string$ Will only match exactly "some string"

a* Will match 0 or more occurrences of "a"

a+ Will match 1 or more occurrences of "a"

. Will match any one character.

.* Will match 0 or more of anything.

.+ Will match 1 or more of anything.

Pattern	Description
some string	Will match match any occurrence of:"some string". e.g.: "Here is some string" will match. "Here is some string in the middle of the text" will match. "some string at the beginning" will match.
^some string	Will match "some string" at the beginning of the text: "Here is some string" will not match. "some string at the beginning"will match
some string$	Will match "some string" at the end of the text: "Here is some string" will match. "some string at the beginning" will not match.
^some string$	Will only match exactly "some string"
a*	Will match 0 or more occurrences of "a"
a+	Will match 1 or more occurrences of "a"
.	Will match any one character.
.*	Will match 0 or more of anything.
.+	Will match 1 or more of anything.